1. Field of the Invention
The present invention relates to a fuel tank fueling device, and more specifically to a fuel cap for a fuel tank fueling device.
2. Description of the Related Art
In conventional fuel tank fueling devices, the fuel cap is opened when fuel is supplied through a fuel inlet pipe. The fuel cap is sealed by pressing a sealing component against the opening (filling neck) of the fuel inlet pipe to prevent fuel vapor in the fuel tank from escaping into the atmosphere. That is, the fuel cap is provided with the sealing component around the periphery of a cylindrical casing. When the fuel cap is screwed onto the opening of the filling neck, the sealing component provides air-tight sealing force, while subject to torque, against the filling neck.
Conventional fuel caps, however, close off the opening by being rotated when attached to the filling neck, so the sealing component is subject to the torque accompanying friction with the filler neck. It has been found that such torque is not readily applied uniformly across the sealing component as a whole, and complicates efforts to improve the sealing properties.
Therefore, there is a need to overcome the drawbacks in the prior art, by providing a fuel tank fueling device that is easier to operate when opening and closing the fuel cap, and that has better properties in sealing the fuel tank against the outside air.
Accordingly, an exemplary embodiment of the present invention provides a fuel tank fueling device for fueling a fuel tank, through the fuel passage of a fuel inlet pipe. The fuel tank fueling device includes: a casing main body detachably attached to the inlet pipe; a handle provided on the casing main body, the handle being operable to open and close the fuel passage; a sealing component interposed between the casing main body and a seat surface of the fuel inlet pipe; a spring constructed and arranged to press the sealing component against the seat surface; and a cam mechanism constructed and arranged to convert an operating force applied to the handle in a closing direction into a spring pressing force, thereby pressing the sealing component against the seat surface.
In the fuel tank fueling device of an exemplary embodiment, the handle is operated to open the casing main body, and the casing main body is taken out of the fuel inlet pipe, so that fuel passes through the fuel passage of the fuel inlet pipe into a tank main body. When the casing main body is then attached to the fuel inlet pipe, and the handle is operated to close it, the cam mechanism converts the rotating force of the handle into force pressing on the seal member via a spring. This causes the spring to press the seal means against the seat surface, sealing the space between the casing main body and the fuel inlet pipe. The sealing component creates a seal between the casing main body and the fuel inlet pipe by means of the pressure of the urging force of the spring, thus allowing the space subject to torque to be shorter than in the prior art, affording more uniform sealing force, and providing better durability.
The fueling mechanism may have a structure in which a guide is mounted on the inner wall of the fuel dispensing device to rotatably and non-extractably support the casing main body against the fuel inlet pipe.
In an exemplary embodiment, the casing main body includes a rotating casing that has the handle and that is rotatably supported by the guide, and a sliding casing that is equipped with the sealing component and that is slidably disposed in the axial direction relative to the rotating casing by means of the guide, and a spring being disposed between the rotating casing and sliding casing.
In an exemplary embodiment of the present invention, the cam mechanism can convert the rotating force when the handle is rotated in the closing direction into pressure force against the sealing component via the spring. That is, in cases where the casing main body is formed separate from the rotating casing and the sliding casing, the cam mechanism may comprise a cam surface, interposed between the rotating casing and sliding casing, whereby the rotating force of the rotating casing is converted to force in the direction in which the sliding casing acts as a seal via the sealing component.
The cam surface may be disposed in a location apart from the sealing component, including a passage passing from the inside the tank main body of the fuel inlet pipe to the outside. This dispenses with the need for providing separate the sealing component on the cam surface, with the cam mechanism, and simplifies the structure.
The cam surface may also include a detent location, where the seat surface is not sealed by the seal means, while the spring is compressed into a state in which the spring force is accumulated, and a sealing location, where the seat surface is sealed by the sealing component when the sliding casing is allowed to slide in the axial direction against the rotating casing upon the release of the urging force accumulated in the spring when the handle is rotated.
Here, the sealing member may create a seal in the direction allowing the seal force to be increased by the urging force of the spring, and may be mounted on the casing main body or the fuel inlet pipe.
The sealing component may also provide greater sealing force by being pressed against the seat surface by the spring. Accordingly, it is not subject to friction force and torque as in the prior art, thus enabling design with higher sealing properties and greater freedom in the materials for the seal member, surface treatment (state), and shape.
The spring may be a coil spring mounted around the periphery of the casing main body.
In an exemplary embodiment, a pressure valve for adjusting the pressure of the tank main body to within the prescribed range may be housed in the casing main body. This structure allows a pressure regulating valve to be provided in a more compact manner.
In an exemplary embodiment of the present invention, there is also provided a fuel tank fueling device for fueling a tank main body, through the fuel passage of an inlet pipe. The fuel tank fueling device of this embodiment includes: a casing main body detachably mounted on the inlet pipe; a handle disposed on the casing main body for opening and closing the fuel passage; a gasket disposed at an upper part of the casing main body for sealing against a seat surface of the inlet pipe; a spring disposed on the casing main body, the spring constructed and arranged to press the gasket against the seat surface; neck engagement threading formed on an inner wall of the inlet pipe; an upper cam ring disposed rotatably on a periphery of the casing main body and the gasket, rotation of the upper cam ring being blocked by the neck engagement threading; and a lower cam ring movably mounted in an axial direction on a periphery of the casing main body, wherein the lower cam ring is guided along the upper ring at the beginning of the rotating operation of the handle, and is positioned by the neck engagement threading after moving in an axial direction when rotated subsequent to the initial rotation, and is guided in such a way as to press the spring while thus positioned so that the gasket seals the seat surface.
In an exemplary embodiment, there is provided a fuel tank fueling device for fueling a tank main body, through the fuel passage of an inlet pipe. The fuel tank fueling device of this embodiment includes: a rotating casing having support ends and a handle for opening and closing the fuel passage, the rotating casing being detachably and rotatably supported at an opening of the inlet pipe; a sliding casing that is slidably supported in an axial direction relative to the rotating casing, the sliding casing having guide protrusions; a gasket mounted at a bottom of the sliding casing, the gasket sealing a seat surface of the inlet pipe; a spring interposed between the rotating casing and the sliding casing, the spring urging the gasket to press against the seat surface; an annular detent disposed on an inner wall of the inlet pipe, the annular detent having insertion notches used for an insertion of the support ends and engaging with the support ends so that the rotating casing is prevented from being removed from the inlet pipe while being rotatably supported; rotation detents located on the inner wall of the inlet pipe, the rotation detents engaging with the guide protrusions on the sliding casing to block rotation of the sliding casing and to guide the sliding casing in an axial direction; and a cam ring interposed between the rotating casing and the sliding casing, the cam ring having a cam surface causing the sliding casing to move in the axial direction so that the gasket seals, pressed by a spring, seals the seat surface when the rotating casing is rotated a predetermined angle, with the rotation of the sliding casing regulated by the rotation detents.
In an exemplary embodiment, the cam surface may be constructed in such a way that the sealing component is pressed by the urging force of the spring at an initial angle of 5 to 90xc2x0, among the operating angle range of 90 to 180xc2x0 of the handle. The ability to obtain high sealing properties at such a smaller angle affords better operation.
Furthermore, when the sealing component is compressed at such a small angle, the repulsion of the seal means is lower, ensuring better sealing properties. That is, the repulsion force of the sealing component increases moderately with the initial compression, but rises rapidly as the compression increases. Thus, rapid compression of the sealing component can result in excess repulsion, preventing adequate sealing properties from being ensured, or can result in the need for greater torque to rotate the fuel cap. In the present invention, however, the cam mechanism gradually releases the urging force of the spring to compress the sealing component, even when the urging force against the spring increases in the initial stages. The repulsion force of the sealing component is thus lower, with no need for considerable torque for rotating the fuel cap, and better sealing properties may be obtained.
In an exemplary embodiment, the cam surface may be constructed in such a way that the urging force of the spring begins when the initial angle is more than 5xc2x0, among the operating angle range of 90 to 180xc2x0 for the handle. This structure allows the casing main body to be mounted in a reliable manner on the inlet pipe because the handle is rotated more than 95xc2x0 and produces no tension under the initial 5xc2x0.
In an exemplary embodiment, the fuel tank fueling device in which the fuel cap is stopped when a vehicle is fueled includes: a cap retainer for retaining the fuel cap; a flexible cord-shaped tether extending from the cap retainer; a vehicle attachment component for attaching the support end of the tether to the vehicle side component; and a detachable component comprising a detent formed on the cap retainer, and an engaged component that is formed on the vehicle attachment component side of the tether and that is detachable from the engagement component.
In an exemplary embodiment, the fuel cap held by the cap retainer may be stopped by a part on the fuel tank fueling device, i.e., the vehicle attachment component or vehicle attachment component side of the tether. There is thus no need to form a detent for stopping the fuel cap on a part of the vehicle such as a lid panel, and no need to consider the height or size of a detent for the fuel tank fueling device when the body thickness is determined.
The cap retainer of the fuel tank fueling device holds the fuel cap. The cap retainer may be in the shape of a ring, for example. The inside diameter of a cap retainer in the form of a ring should be larger than the outside diameter of the leg of the fuel cap, or the cap retainer should be fitted to a corner of the head of the fuel cap so that the fuel cap may be rotated relative to the cap retainer. This prevents the cap retainer from impeding the rotation of the fuel cap when the fuel cap is removed from or attached to the fueling opening.
The tether of the fuel tank fueling device may extend from the cap retainer, may be flexible, and may be in the form of a cord. The tether may extend from either of the end surfaces or from the outer peripheral surface of the cap retainer. When the tether extends from the outer peripheral surface of the cap retainer, the cap retainer and tether are located in the same plane, thereby allowing the fuel tank fueling device to be made thinner (lower). When the cap retainer is in the form of a ring, the tether may extend at the desired angle from the cap retainer. However, in consideration of the strength and the like with which the tether is bound to the cap retainer, etc., the tether preferably extends in such a way that the line of extension conforms to the hypotenuse of the ring-shaped cap retainer. The thickness and length of the tether should be enough to allow the tether to be easily bent when one of the detachable parts provided on the cap retainer or the like is attached to and detached from the other provided on the vehicle attachment component or the like.
The vehicle attachment component of the fuel tank fueling device attaches the tip of the tether to the vehicle. The vehicle is the part of the body that is exposed when a lid panel is opened, or a lid panel that opens to remove the fuel cap from the fueling opening during fueling, for example. The vehicle attachment component may be formed unitarily with, or separately from, the tether. When the vehicle attachment component is formed unitarily with the tether, the vehicle attachment component may be made of a clip including a base with a flat contact surface forming part of the tether, a diametrically expandable tubular component protruding from the contact surface, and a core that is inserted into the tubular component to diametrically expand the tubular component so that it engages with the edge of the through hole of the lid panel. This allows the structure of the vehicle attachment component and the tip of the tether to be made more compact.
The core may be connected by a U-shaped connector to the tip of the tether. This may prevent the core from being lost when the core temporarily inserted into the tubular component of the clip main body is taken out of the tubular component. The cap retainer, tether, vehicle attachment component, and detachable component may be unitarily formed of a soft resin or the like.
An engagement component may be formed on the outer peripheral surface of the core, allowing the core to be retained by the tubular component while inserted midway into the tubular component. This prevents the core from being lost when the core and tubular component are not connected, and also prevents the core, when connected to the tubular component, from dangling down from the tip of the tether and interfering with the surrounding component. The end of the core base and the engaged component may be connected by a connecting piece when the fuel tank fueling device is shipped or stored, and the connecting piece may be broken off when used. This may prevent the core from dangling down, even when no means has been provided to hold the core while inserted half way into the clip main body as described above.
One of the detachable members of the fuel tank fueling device may be formed on the cap retainer or on the cap retainer side of the tether. When one of the detachable components is formed on the cap retainer, the location where it is formed may be selected as desired according to whether lid panel and fuel cap are on the left or right side surface of the vehicle, or a location where the tether extends, etc. In other words, the fuel tank fueling device as a whole is curved in the shape of a reverse C when the lid panel or the like is on the left side surface of the vehicle, and is curved in the shape of a C when the lid panel or the like is on the right side surface of the vehicle. By contrast, the other detachable member may be formed on the vehicle attachment component, and may be formed on the vehicle attachment component side of the tether. One of the detachable members may be formed on the cap retainer, and the other may be formed on the vehicle attachment component, allowing a shorter tether to be made.
The specific structure of the detachable component may be managed so that the detent is readily operated and then released when the tether is bent to stop the cap retainer near the vehicle attachment component. For example, one of the detachable components may protrude radially and/or axially on the cap retainer, and the other may be formed on the side opposite the surface facing the lid panel of the tether near the vehicle attachment component. A plurality of the one detachable component may be provided on cap retainers to allow the fuel tank fueling device to be jointly used when lid panels and fuel caps are on both the left or right sides of a vehicle, in order to make it easier to detach the other.
The cap retainer, tether, vehicle attachment component and detachable components may be constructed in such a way that the tether, vehicle attachment component, and detachable components are on the inside surface of the ring-shaped cap retainer when the fuel tank fueling device is not being used. This makes it easier to ship and store the fuel tank fueling device, and makes it easier to form the fuel tank fueling device by injection molding or the like.
In an exemplary embodiment, the fuel tank fueling device may comprise a clutch disposed between the casing main body and the handle, and that produces an engaged state in which the casing main body is made to rotate in a unitary manner when the handle is rotated, or an unengaged state in which the casing main body does not rotate in a unitary manner even though the handle is rotated, and a spring urging the clutch in the direction resulting in an unengaged state.
In order to take the fuel cap out of the tank opening in this embodiment, the handle is pressed against the urging force, resulting in the engagement of the clutch, and the handle is rotated, with the clutch in an engaged state. Upon the rotation of the handle, the rotating force is transmitted to the casing, and the casing is fitted to the opening of the tank. The handle is pressed against the urging force of the spring to set the clutch in an engaged state, and is rotated from this engaged state in the direction opposite the opening direction take off the fuel cap and open the tank opening. The clutch is thus pressed into an engaged state to open and close the fuel cap.
While the fuel cap is mounted on the tank opening, the urging force of the spring keeps the clutch in an unengaged state. As a result, even when the handle is subject to force in the rotating direction by unexpected external force, the clutch is in an unengaged state, so the handle turns without catching. The casing thus receives no rotating force from any external force acting on the handle, allowing the tank opening to be kept in a closed state. In other words, even when unexpected external force acts on the fuel cap, the fuel cap will not come loose, and the seal may be preserved.
While the clutch is in an unengaged state, the handle may be rotated without catching, so as to be aligned. The user can thus rotate the handle to the preferred position while the clutch is in an unengaged state, further improving opening and closing operations.
An exemplary embodiment of the clutch comprises an array of gears, such that the gears either interlock or are not interlocked, so as to produce either an engaged or unengaged state, at a location where the handle and casing main body are opposite each other.
An exemplary embodiment of the spring comprises a cantilever piece unitarily protruding from the handle, where one end of the cantilever piece presses on the handle, urging against the handle, or a cantilever piece unitarily protruding from the handle, where one end of the cantilever piece presses on the casing, urging it against the casing. The spring can thus be unitarily formed with the handle or casing to avoid increasing the number of parts.
In an exemplary embodiment, a fueling device featuring the use of the fuel cap, the fuel inlet pipe, handle, and cantilever piece are formed of a conductive substance, and the cantilever piece is located so as to come into contact with the fuel inlet pipe. This structure allows the cantilever piece to act as a ground path through which the charge building up in the handle can escape to the fuel inlet pipe. The cantilever piece thus serves as a spring and a ground path, making it unnecessary to provide a separate ground path, so that the structure is simpler.